The steps involved in manufacturing semiconductor components are typically divided into two broad categories: front-end processing steps and back-end processing steps. Front-end processing steps include photolithography, etching, doping, and passivation, whereas back-end processing steps include chip separation (i.e., dicing), chip mounting, and encapsulation. Encapsulation is an important step because it provides a means of protecting a semiconductor chip from mechanical and environmental stresses. A technique for encapsulating a semiconductor chip is to mount it to a support substrate in a flip-chip orientation and cover it with a lid. The lid has a lip for coupling to the support substrate. The lid is placed over the semiconductor chip such that the lip contacts an adhesive material disposed on the support substrate. The combination of the support substrate, semiconductor chip, and lid form a semiconductor assembly. A force is applied to the lid and the semiconductor assembly is placed in an oven to cure the lid adhesive material.
A drawback with this technique is that there is a mismatch between the radius of curvature of a semiconductor chip mounted to a support substrate and the radius of curvature of the lid. The difference between the coefficient of thermal expansion of the support substrate and the semiconductor chip causes the chip to warp at room temperature. A warped semiconductor chip has a larger radius of curvature than a non-warped semiconductor chip. The larger radius of curvature inhibits wetting of the thermal interface material near the center of the semiconductor chip. The lack of wetting decreases the amount of heat transferred from the semiconductor chip to the lid, which degrades the performance of the semiconductor component.
Accordingly, what is needed is a semiconductor component and a method for improving wetting of a thermal interface material in a semiconductor component thereby enhancing heat dissipation properties of the semiconductor component.